So I have a custom PCB which was designed for the ATMega324PA that I'm trying to troubleshoot. When we populate the board with the 324PB chip, it is proogrammed and behaves properly. However, when we put in the 324PA, the programmer cannot verify the flash. It sometimes gets as far as address 0x1954 (which is 6484 out of ~11 000 bytes total) but will fail randomly along the Flash.
As far as I know, the only difference in the hook ups for the PA and the PB is the need for extra filtering capacitors on the two additional Vcc and GND lines. W have those capacitors, but the PB chips all work and the PA chips don't. Maybe this specific behavior is known and you guys can quickly tell me precisely how I am being an idiot tody. Or maybe not, in which case I guess we wait the 26 week lead time for 324PBs, because circuit boards are voodoo to me.
Thanks in advance!